add log to file option -l

upper/services/tunnel/tunnel.go

@@ -1,7 +1,7 @@
 package tunnel
 
 import (
-	"errors"
+	"io"
 	"net"
 
 	"github.com/sirupsen/logrus"
@@ -72,7 +72,7 @@ func (s *Tunnel) Read(p []byte) (int, error) {
 			return copy(p, d[:len(p)]), nil
 		}
 	}
-	return 0, errors.New("reading reaches nil")
+	return 0, io.EOF
 }
 
 func (s *Tunnel) Stop() {

upper/services/tunnel/tunnel_test.go

@@ -3,6 +3,7 @@ package tunnel
 import (
 	"crypto/rand"
 	"encoding/hex"
+	"io"
 	"testing"
 
 	curve "github.com/fumiama/go-x25519"
@@ -84,6 +85,17 @@ func TestTunnel(t *testing.T) {
 		t.Fatal("error: recv 4096 bytes data")
 	}
 
+	sendb = make([]byte, 65535)
+	rand.Read(sendb)
+	n, _ := tunnme.Write(sendb)
+	t.Log("write", n, "bytes")
+	buf = make([]byte, 65535)
+	n, _ = io.ReadFull(&tunnpeer, buf)
+	t.Log("read", n, "bytes")
+	if string(sendb) != string(buf) {
+		t.Fatal("error: recv 65535 bytes data")
+	}
+
 	tunnme.Stop()
 	tunnpeer.Stop()
 }